F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust

F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control

F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters

B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES

B60K13/00—Arrangement in connection with combustion air intake or gas exhaust of propulsion units

B60K13/04—Arrangement in connection with combustion air intake or gas exhaust of propulsion units concerning exhaust

E—FIXED CONSTRUCTIONS

E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING

E02F—DREDGING; SOIL-SHIFTING

E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00

F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series

F01N13/011—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more purifying devices arranged in parallel

F01N13/1805—Fixing exhaust manifolds, exhaust pipes or pipe sections to each other, to engine or to vehicle body

F01N13/1811—Fixing exhaust manifolds, exhaust pipes or pipe sections to each other, to engine or to vehicle body with means permitting relative movement, e.g. compensation of thermal expansion or vibration

F01N13/1816—Fixing exhaust manifolds, exhaust pipes or pipe sections to each other, to engine or to vehicle body with means permitting relative movement, e.g. compensation of thermal expansion or vibration the pipe sections being joined together by flexible tubular elements only, e.g. using bellows or strip-wound pipes

F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust

F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust

F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control

F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters

F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES

F01N2340/00—Dimensional characteristics of the exhaust system, e.g. length, diameter or volume of the apparatus; Spatial arrangements of exhaust apparatuses

F01N2340/02—Dimensional characteristics of the exhaust system, e.g. length, diameter or volume of the apparatus; Spatial arrangements of exhaust apparatuses characterised by the distance of the apparatus to the engine, or the distance between two exhaust treating apparatuses

F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES

F01N2340/00—Dimensional characteristics of the exhaust system, e.g. length, diameter or volume of the apparatus; Spatial arrangements of exhaust apparatuses

F01N2340/04—Dimensional characteristics of the exhaust system, e.g. length, diameter or volume of the apparatus; Spatial arrangements of exhaust apparatuses characterised by the arrangement of an exhaust pipe, manifold or apparatus in relation to vehicle frame or particular vehicle parts

F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust

F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters

F01N3/033—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices

F01N3/035—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices with catalytic reactors, e.g. catalysed diesel particulate filters

F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust

F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus

F01N3/28—Construction of catalytic reactors

F01N3/2882—Catalytic reactors combined or associated with other devices, e.g. exhaust silencers or other exhaust purification devices

Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE

Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE

Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection

Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE

Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

Y02T10/00—Road transport of goods or passengers

Y02T10/10—Internal combustion engine [ICE] based vehicles

Y02T10/20—Exhaust after-treatment

Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE

Abstract

Two sets of assemblies (2a, 2b) are arranged so that the diesel particulate collection filter device (3) of the assembly (2a), the selective reduction catalyst device (4) of the assembly (2a), the selective reduction catalyst device (4) of the assembly (2b), and the diesel particulate collection filter device (3) of the assembly (2b) are arranged side by side in sequence. Exhaust tubes (6) are provided so as to extend upward from the exhaust openings (6a) of both the selective reduction catalyst device (4) of the assembly (2a) and the selective reduction catalyst device (4) of the assembly (2b). The two exhaust tubes (6) are located on an imaginary plane (E) perpendicular to the longitudinal directions (B1, B2) of the selective reduction catalyst devices (4) of the assemblies (2a, 2b). As a result of this configuration in which the two sets of assemblies (2a, 2b) are provided, the air intake position of an engine (10) can be easily set to a position at which the engine (10) is less likely to suck in exhaust gas discharged from the engine (10).

Description

Engine unit and the working vehicle

The present invention relates to an engine unit and a work vehicle.

Hydraulic excavator, bulldozer, in the work vehicle such as a wheel loader, the exhaust treatment device is mounted. The exhaust treatment device, for example, diesel particulate filter device (DPF), diesel oxidation catalyst device (DOC), and the like selective reduction catalyst device (SCR) is present.

Work vehicle equipped with an exhaust treatment device is disclosed, for example, in JP 2012-097413 JP (see Patent Document 1).

In this publication, it is arranged tables interposed support legs on the upper frame, the first exhaust treatment device and the second exhaust treatment device is arranged to an exhaust treatment unit on the table. The engine and the first exhaust treatment device are connected by a connecting pipe.

JP 2012-097413 JP

Intake position of the air used for combustion of the engine is preferably a position that does not breathe exhaust of the engine.

Here, in the vehicle equipped with a large engine may have the exhaust gas treatment capability becomes insufficient, it is conceivable to provide a plurality of exhaust treatment unit in order to increase the exhaust gas treatment capability. However, when providing a plurality of exhaust treatment unit, the position of the exhaust gas becomes a multiple set of intake position becomes difficult.

The present invention has been made in view of the above problems, its object is, in the configuration provided with a plurality of exhaust treatment unit, the suction position of the air used for combustion in the engine, the suction position hardly exhaust of the engine it is that to provide an easy engine unit and the work vehicle to be determined.

Engine unit of the present invention includes an engine, a first exhaust treatment device, and the second exhaust treatment device, and a third exhaust treatment device, and the fourth exhaust treatment device, a first exhaust pipe and a second exhaust pipe It is provided. First exhaust treatment apparatus for treating exhaust gases from the engine. The second exhaust treatment device processes the exhaust gas passed through the first exhaust treatment device. Third exhaust treatment apparatus for treating exhaust gases from the engine. Fourth exhaust processing device for processing the exhaust gas passed through the third exhaust treatment device. The first exhaust pipe extends upward from the outlet of the second exhaust treatment device. The second exhaust pipe extends upward from the outlet of the fourth exhaust treatment device. The first to fourth exhaust treatment device, so that each longitudinal direction is parallel, the first exhaust treatment device, the second exhaust treatment device, the fourth exhaust treatment device, are arranged in the order of the third exhaust treatment device there. Each of the second exhaust pipe of the first exhaust pipe and the fourth exhaust treatment device of the second exhaust treatment apparatus, the same end side in the longitudinal direction of the longitudinal direction and a fourth exhaust gas treatment apparatus of the second exhaust treatment device side by side are arranged.

According to the engine unit of the present invention, since the first to fourth exhaust treatment device is provided, it is possible to increase the exhaust gas treatment capability, sufficient exhaust gas treatment capability in a vehicle equipped with a large engine it is possible to obtain.

The first and second exhaust pipes are provided in each of the second and fourth exhaust treatment device adjacent to each other and the first and second exhaust pipe identical in the longitudinal direction of each of the second and fourth exhaust treatment device It is arranged in the end side. Therefore, it is possible to approach the positions of the first and second exhaust pipes to each other, the flow direction of the exhaust gas is likely to be grasped, the intake position of the air used for combustion in the engine, the suction position hardly exhaust of the engine it becomes easy to determine the.

In the above engine unit, the first exhaust treatment device and the second exhaust treatment device, the second exhaust treatment device and the fourth exhaust treatment device, and a fourth exhaust gas treatment apparatus and spacing, respectively a plan view and the third exhaust treatment device They are spaced apart have.

This makes it possible to the first to fourth exhaust treatment device arranged packed while spaced from each other.

In the above engine unit, the second relay connecting the first relay connection pipe connecting the first exhaust treatment device and the second exhaust treatment device, between the third exhaust treatment device and the fourth exhaust treatment device and connecting pipe are further provided. In plan view, the distance between the first exhaust treatment device and the second exhaust treatment device, the distance between the second exhaust treatment device and the fourth exhaust treatment device, and a fourth exhaust treatment device and the distance between the third exhaust treatment device each is smaller than the diameter of the diameter of the first relay connection pipe and the second relay connecting tube.

It is possible to arrange thereby from the first stuffed fourth exhaust treatment apparatus, it is possible from the first to place the fourth exhaust treatment device compact.

Working vehicle according to the present invention includes an engine unit according to any of the above. According to the work vehicle of the present invention, in a structure in which a plurality of exhaust treatment unit, it is easy to determine the intake position of the engine the suction position hardly exhaust of the engine.

According to the present invention described above, the exhaust treatment units in plurality configuration, and the intake position of the air used for combustion in the engine, easy engine to determine the suction position hardly exhaust of the engine unit and it is possible to realize a work vehicle.

The configuration of a hydraulic excavator according to an embodiment of the present invention is a perspective view schematically showing. Enlarged near the engine room of a hydraulic excavator shown in FIG. 1 is a partially transparent perspective view showing a perspective and with the interior of the engine exhaust treatment structure. It is a schematic perspective view showing the engine and the exhaust processing structure of the hydraulic excavator from the rear diagonal direction shown in FIG. It is a plan view schematically showing a configuration of an exhaust processing structure from above shown in FIG. It is a rear view schematically showing a connecting pipe between the engine and the exhaust processing structure from the rear shown in FIG. It is a rear view schematically showing the configuration of the engine and exhaust treatment structure is supported on the frame independently of each other from the rear (back) (rear view). The configuration in which the exhaust treatment structure and the engine is supported independently of one another to the frame is a side view schematically showing from the side. The exhaust treatment structure is a exploded perspective view showing the structure of a support for supporting the frame. And mixing pipe and the urea water tank exhaust treatment structure is a schematic perspective view showing a structure connected by urea water pipe. The configuration of a modification of the connecting tube is a rear view schematically showing. A configuration in which the exhaust processing structure is supported by the engine is a perspective view schematically showing. The air cleaner is a schematic perspective view showing a state that is connected to the intake side of the engine from the oblique rear. The air cleaner and the umbrella portion is a schematic perspective view showing from the front showing the external configurations outside the engine hood. An air cleaner is furnished inside the engine hood, and is a schematic perspective view illustrating an umbrella portion from the front showing a structure located outside the engine hood. An air cleaner is furnished inside the engine hood, and is a schematic perspective view showing from the front showing the configuration without the umbrella portion.

Hereinafter will be described with reference to FIG embodiments of the present invention. The configuration of the hydraulic excavator will be described with reference to FIG. 1 first as an example of a work vehicle in the embodiment of the present invention, the present invention is applied to a work vehicle having an engine unit comprising an exhaust treatment unit, such as a wheel loader, bulldozer possible it is.

Note In the following description of the drawings, the front-rear direction refers to the front-rear direction of the hydraulic excavator 30. In other words, the longitudinal direction means the longitudinal direction as viewed from the driver seated in the driver's seat of the cab 31a. Further, the left-right direction or side, means the vehicle width direction of the hydraulic excavator 30. In other words, the left-right direction, the vehicle width direction, or the lateral, a left and right directions as viewed from above the driver. Further, in the following figures, the arrow X in the drawing in the longitudinal direction, in the arrow Y in the lateral direction indicates the vertical direction by an arrow Z.

Figure 1 is a perspective view schematically showing the configuration of a hydraulic excavator according to an embodiment of the present invention. Referring to FIG. 1, the hydraulic excavator 30 in this embodiment comprises a lower traveling body 40, an upper swing body 31, mainly has a working machine 32. Working vehicle body is constituted by a lower traveling body 40 and the upper swing body 31.

Undercarriage 40 includes a pair of left and right crawler belts 50. Each of the pair of left and right crawler unit 50 has a track. The pair of left and right crawler unit 50 is a hydraulic excavator 30 is configured to be self-propelled by driving rotation.

Upper revolving body 31 is installed pivotably with respect to the undercarriage 40. The upper rotating body 31 has a cab 31a in the front left (vehicle front side), it has a rear engine and counterweight 31c for housing the engine unit (after vehicle) (engine, such as exhaust treatment structures) doing. Upper side of the engine room is covered by an engine hood 31b. Counterweight 31c is disposed behind the engine room.

Working machine 32 is pivotally supported on the front side of the upper frame 31, for example a boom 32a, arms 32b, bucket 32c, and a like hydraulic cylinder. Proximal end of the boom 32a is rotatably connected to the upper swing body 31. The base end portion of the arm 32b is rotatably connected to the tip of the boom 32a. Bucket 32c is rotatably connected to the distal end of the arm 32b. Work machine 32 by each of the boom 32a, the arm 32b and the bucket 32c is driven by a hydraulic cylinder can be driven.

It will now be described with reference to FIGS. 2-9 the structure of an engine unit mounted on the hydraulic excavator (including engine, the exhaust treatment structures and connecting tube).

Figure 2 is an enlarged vicinity of the hydraulic excavator engine room shown in FIG. 1 is a partially transparent perspective view showing a perspective and with the interior of the engine exhaust treatment structure. Referring to FIG. 2, in the engine room, the above as the engine unit is disposed. The engine unit includes an engine 10, an exhaust processing structure 1, and the supporting structure 20A, the first and second connecting pipe 7a, has 7b (such as Fig. 3) and mainly.

Engine 10 is, for example, large diesel engines having a total engine more than 20 liters.

The combination of the first and second exhaust treatment device 3 and 4, diesel particulate filter device, a diesel oxidation catalyst device, and it is possible to select an appropriate combination from the selective reduction catalyst device. The combination of the third and fourth exhaust treatment device 3, 4 is also diesel particulate filter device, it is possible to select an appropriate combination diesel oxidation catalyst device, and a selective reduction catalyst device.

In this embodiment, each of the first and third exhaust gas treatment apparatus 3, 3 is a diesel particulate filter device for example, each of the second and fourth exhaust treatment device 4,4, for example the selective reduction catalyst device 4. Also each of the first and second relay connecting tube 5 and 5 is, for example, mixing pipe.

Diesel particulate filter device 3 is a device for treating exhaust from the engine 10, a filter (not shown) and a heater attached to the filter (not shown) mainly have. Diesel particulate filter device 3, the particulate matter contained in exhaust gas of the engine is collected by the filter, it is configured to burn the collected particulate matter. Filter, for example, is made from ceramic.

Selective catalytic reduction device 4 is a device for treating exhaust from the engine 10 is for the example urea water as the reducing agent by hydrolyzing the reduction of nitrogen oxides NO x. Selective catalytic reduction device 4, in principle, that the ammonia (NH 3) is reduced to nitrogen and (N 2) and water (H 2 O) by chemical reaction with the nitrogen oxides (NO x) it is an application. Since however the gain ammonia hydraulic excavator 30 is dangerous, as the reducing agent tank, for example, a urea water tank 21 containing the urea water (Fig. 9) is mounted on the hydraulic excavator 30. However reducing agent is not limited to urea water, as long as it can reduce nitrogen oxides NO x.

Mixing pipe 5 is connected between the diesel particulate filter device 3 and selective catalytic reduction device 4. That is, a diesel particulate filter device 3 and a selective reduction catalyst device 4 are connected by the mixing pipe 5. The mixing pipe 5, the exhaust flowing from the diesel particulate filter device 3 to the selective reduction catalyst device 4, for example, by injecting urea water is a portion for mixing the urea in the exhaust.

Stack 6 is connected to the exhaust port 6a of the selective reduction catalyst device 4 in the selective reduction catalyst device 4 so as to extend upward. Stack 6 is for discharging exhaust after passing through the the diesel particulate filter device 3 and a selective reduction catalyst device 4 to the atmosphere. The chimney 6 protrudes upward from the engine hood 31b.

The two sets of assemblies 2a, 2b are, in plan view, diesel particulate filter device 3 of the assembly 2a, selective catalytic reduction device 4 of the assembly 2a, assembly 2b of the selective reduction catalyst device 4, the assembly 2b It is disposed of so as to line up in the order of diesel particulate filter device 3.

Assembly 2a of the two sets, 2b is supported so as to be located on the engine 10 by the support material 20A. The supporting structure 20A, which supports the exhaust treatment structure 1, a plate board 11 placed on the body frame, the vertical frame 12, the lateral frame 13, a sub-bracket 14, Small brackets (shown not) and a. Details will be described later of the configuration of the supporting structure 20A.

Figure 3 is a schematic perspective view showing the engine of the hydraulic excavator shown in FIG. 1 and the exhaust processing structure obliquely from the rear. 3, in the engine unit of the present embodiment, between the exhaust treatment structure 1 and the engine 10, first and second connecting pipe 7a, are connected by 7b.

That is, the first connecting pipe 7a are leading exhaust gas from the engine 10 to the diesel particulate filter device 3 of the assembly 2a. The second connection pipe 7b are leading exhaust gas from the engine 10 to the diesel particulate filter device 3 of the assembly 2b.

First and second connecting pipe 7a, each 7b is retractable bellows portion 7aa, a bellows expansion joint having 7ba. First and second connecting pipe 7a, each 7b is made of steel from the viewpoint of heat resistance and corrosion resistance, such as stainless steel.

The first connecting pipe 7a, a bellows portion 7aa, for example, two bellows parts 7aa, 7aa is provided. The second connection pipe 7b, a bellows portion 7ba, for example, two bellows parts 7ba, 7ba are provided. However, the first and second connecting pipe 7a, a bellows portion is provided in each 7b 7aa, number of 7ba is not limited thereto, but may be one or three or more. Further, the number of bellows portions 7aa provided in the first connecting pipe 7a, the number of bellows part 7ba provided in the second connection pipe 7b may be the same or may be different.

Figure 4 is a plan view schematically showing the configuration of an exhaust processing structure shown in FIG. 3 from above. Referring to FIG. 4, the assembly 2a, 2b each diesel particulate filter device 3 has a substantially cylindrical outer shape. The assembly 2a, each of the selective reduction catalyst device 4 and 2b has a substantially cylindrical outer shape.

It extends longer than the radial in the two diesel particulate filter device 3 and the central axis of each of the two component devices 3 and 4 the cylindrical shapes of the selective reduction catalyst device 4 A1, A2, B1, B2 direction. Therefore, the longitudinal direction of the respective component devices 3 and 4 corresponds to the direction of each of the central axis A1, A2, B1, B2.

Each configuration device 3 and 4, in a plan view, each of the longitudinal direction are arranged so as to parallel (extending parallel) to each other. That each of the central axis A1, A2, B1, B2 of component devices 3 and 4 are arranged to parallel (extending parallel) to each other. If the central axis A1, A2, B1, B2 of each of the component devices 3 and 4 if in parallel (parallel running) to each other, may be parallel it does not have to be parallel to each other.

On one end side of the longitudinal two each diesel particulate filter device 3 directions A1, A2, the first and second connecting pipe 7a, the inlet port 3a of each 7b are connected is provided. The two diesel particulate filter device each longitudinal A1, the other end of the A2 of 3, the exhaust port 5a is provided with the mixing pipe 5 is connected. Each Thus two diesel particulate filter device 3, the longitudinal A1, A2 of the diesel particulate filter device 3 as indicated by arrows S1, S2 are configured such that the movement path of the exhaust.

On one end side of each of the two longitudinal selective reduction catalyst device 4, the air inlet 5b is provided with the mixing pipe 5 is connected. The two selective reduction catalyst device each longitudinal B1, B2 other end of the 4, the exhaust port 6a is provided with an exhaust pipe 6 is connected. Thus each of the two selective reduction catalyst device 4 in the longitudinal direction B1, B2 of the selective reduction catalyst device 4 as shown by arrow S3, S4 is configured such that the movement path of the exhaust. The moving direction of exhaust gas in the selective reduction catalyst device 4 is the moving direction of exhaust gas in the diesel particulate filter device 3 are the same direction.

Also each of the two mixing pipes 5, the longitudinal direction of the mixing pipe 5 as indicated by an arrow S5, S6 are configured such that the movement path of the exhaust. Note the direction of movement of the exhaust gas in the mixing pipe 5 is moved the opposite direction of exhaust gas in each of the diesel particulate filter device 3 and selective catalytic reduction device 4.

The two diesel particulate filter device 3 and the two selective reduction catalyst device 4 are arranged along the direction (e.g., perpendicular direction) crossing the respective longitudinal A1, A2, B1, B2. More specifically, each longitudinal and two diesel particulate filter device 3 and the two selective reduction catalyst device 4 A1, A2, B1, B2 extends in the longitudinal direction of the hydraulic excavator 30 (X-direction) It is arranged along the lateral direction of the hydraulic excavator 30 (Y direction) and two diesel particulate filter device 3 and the two selective reduction catalyst device 4.

Also with respect to the exhaust passage in the exhaust treatment structure 1, the exhaust moves from one end side in the longitudinal direction A1 of the diesel particulate filter device 3 to the other end side. Thereafter, the exhaust reaches the one end side in the longitudinal direction B1 of the mixing pipe 5 selective reduction catalyst device is folded in the opposite direction through 4. Thereafter, the exhaust is folded in the opposite direction again selective reduction catalyst device 4 and is exhausted to move to the other end side from the exhaust pipe 6 from one end side in the longitudinal direction B1 of the selective reduction catalyst device 4. The exhaust path so becomes in plan view for example S-shaped.

Each of the two diesel particulate filter device 3 of the intake port 3a is located on the same side of the longitudinal direction A1, A2 (lower side in the figure). In the case of two diesel particulate filter device each longitudinal A1, A2 of 3 mutually parallel in a plan view, each of the two diesel particulate filter device 3 of the intake port 3a is the longitudinal direction A1, A2 It is arranged to include a plane C of the virtual orthogonal to both the.

Each of the exhaust pipe 6 of the exhaust pipe 6 and the assembly 2b of the assembly 2a is in both the longitudinal direction B2 of the longitudinal B1 and selective reduction of the assembly 2b catalytic converter 4 of the selective reduction catalyst device 4 of the assembly 2a lined to include a virtual plane E orthogonal is located. That each of the two exhaust pipe 6, without interposing other exhaust treatment device therebetween in a plan view, and two selective reduction catalyst device longitudinally B1, the same end side of B2 4 (inlet 5b It is arranged so as to approach each other by being located on the opposite side) and.

In plan view, diesel particulate filter device 3 and selective catalytic reduction device 4 of the assembly 2a, to the imaginary straight line D extending in the longitudinal direction in between the two selective reduction catalyst device 4, a diesel particulate assembly 2b It is arranged in the collecting filter device 3 and a selective reduction catalyst device 4 and the line symmetry.

The spacing GA between diesel particulate filter device 3 and selective catalytic reduction device 4 in assembly 2a, and the spacing GB between 4 selective reduction catalyst device is smaller than the diameter D1, D2 of each of the two mixing pipes 5 . The spacing GA between diesel particulate filter device 3 and selective catalytic reduction device 4 in assembly 2b, and the distance GB between 4 selective reduction catalyst device is smaller than the diameter D1, D2 of each of the two mixing pipes 5 .

In plan view, overlaps assembly 2a, 2b also each interval GA between the diesel particulate filter device 3 and selective catalytic reduction device 4 in each assembly 2a, in 2b, and each of the mixing pipe 5 .

Figure 5 is a rear view schematically showing a connecting pipe and engine shown in FIG. 3 and the exhaust processing structure from the rear of the vehicle body (the back) (rear view). Referring to FIG. 5, one end 7ab of the first connection pipe 7a is connected to the exhaust port 9a of the engine 10 by interposing a branch pipe 8 and the supercharger 9. The other end of the first connection pipe 7a is connected to the intake port 3a of the diesel particulate filter device 3 of the assembly 2a.

The other end of the first connecting pipe 7a may be directly connected without interposing another pipe to the intake port 3a of the diesel particulate filter device 3 of the assembly 2a, also interposed another pipe or it may be indirectly connected to. One end 7ab of the first connecting pipe 7a may be connected to the exhaust port 9a of the engine 10 without intervening supercharger 9.

The first connecting pipe 7a is a transverse extending portion extending from one end 7ab the Y direction, and an inclined portion extending inclined at a predetermined angle with respect to the Y direction from the lateral extending portion, Z-direction from the inclined portion and a connected longitudinally extending portion on diesel particulate filter device 3 extends to. Bellows 7aa is provided in the inclined portion.

One end 7bb of the second connection pipe 7b is connected to the exhaust port 9a of the engine 10 by interposing a branch pipe 8 and the supercharger 9. The other end of the second connection pipe 7b is connected to the intake port 3a of the diesel particulate filter device 3 of the assembly 2b.

The other end of the second connection pipe 7b may be directly connected without interposing another pipe to the intake port 3a of the diesel particulate filter device 3 of the assembly 2b, also interposed another pipe or it may be indirectly connected to. One end 7bb of the second connection pipe 7b can be connected to the exhaust port 9a of the engine 10 without intervening supercharger 9.

The second connection pipe 7b has a first lateral extending portion extending from one end 7bb the Y direction, a first longitudinal extending portion extending in the Z-direction from the first lateral extending portion, the first from the vertical extending portion and the first lateral extending portion and the second lateral extending portion extending in the Y direction so as to guide the exhaust gas in the opposite direction, extending from the second lateral extending portion in the Z direction and a second longitudinal extending portion connected to the diesel particulate filter device 3 Te. That is, the second connection pipe 7b, after extending to one side of the Y-direction at a first lateral extending portion, and a second lateral extending portion folding direction opposite to the one side thereof. Bellows 7ba is provided on the second lateral extending portion.

At least a portion of the assembly 2b is arranged at a position overlapping the engine 10 in a plan view. Diesel particulate filter device 3 of the assembly 2b, selective catalytic reduction device 4, the mixing pipe 5 and the exhaust pipe 6 is disposed at a position overlapping the engine 10 in a plan view, located directly above the area of ​​the engine 10 It is.

On the other hand, the assembly 2a is disposed in a position which does not overlap with the engine 10 in a plan view. Diesel particulate filter device 3 of the assembly 2a, selective catalytic reduction device 4, the mixing pipe 5 and the exhaust pipe 6 is disposed at a position which does not overlap with the engine 10 in a plan view, avoiding the area just above the engine 10 It is arranged Te.

The first connection pipe 7a is connected to the diesel particulate filter device 3 of the assembly 2a via the region directly below arrangement region R2 in FIG. The second connection pipe 7b is connected to the diesel particulate filter device 3 of the assembly 2b via the region directly below arrangement region R2 in FIG.

The A region directly below arrangement region R2, with respect to the arrangement region R2, the two selective reduction catalyst device 4, 4 facing each other direction (e.g., Y direction) and two longitudinal each of the selective reduction catalyst device 4,4 B1, it is B2 (eg X-direction) to a region located in the direction (Z direction) perpendicular to the surface formed from a.

That is, the first connecting pipe 7a, 7b both is via at least a partial area of ​​the region directly below the selective reduction catalyst device 4 in the region directly below and assemblies 2b of the selective reduction catalyst device 4 of the assembly 2a.

First and second connecting pipe 7a, each end (engine-side of the connection end) of 7b 7ab, 7bb, it is preferable that the positioned directly below the region R1 of the exhaust treatment structure 1, also below the arrangement region R2 it is more preferably located in the region.

That first and second connecting tubes of each end 7ab, 7bb is beneath a region between the at least part or assembly 2a and assembly 2b, beneath the region directly below the region and assemblies 2b of the assembly 2a R23 it is preferable that the positioned at least in part. The respective end 7ab of the first and second connecting pipes, 7bb, at least a portion of the region directly below R21, R22 of the selective reduction catalyst device 4 of the selective reduction catalyst device 4 and assemblies 2b of the assembly 2a, or assembly it is more preferably located on at least a part of the region directly below R23 between 2a selective reduction catalyst device 4 and the assembly 2b selective reduction catalyst device 4 in.

Next, the structure for supporting the engine and the exhaust processing structure will be described with reference to FIGS.

6 and 7 are a side view schematically showing the structure of the engine and exhaust treatment structure is supported on the frame independently of one another rear view schematically showing from the rear, and from the side. With reference to FIGS. 6 and 7, in this embodiment, it is supported on the vehicle body frame 15 independently of one another from the engine 10 and the exhaust processing structure 1.

Specifically, the engine 10 is supported by the vehicle body frame 15 by interposing a rubber damper 16. Vibration of the engine 10 from being transmitted to the vehicle body frame 15 is suppressed by the rubber damper 16. The exhaust treatment structure 1 is supported on the body frame 15 by the support material 20A.

Figure 8 is an exploded perspective view showing the structure of a support for supporting an exhaust processing structure to the frame. Referring to FIG. 8, as the supporting structure 20A is shown in FIG. 8, the two plates plate 11, and four vertical frames (pillar member) 12, a transverse frame 13, and two sub-bracket 14, a plurality and a small bracket 141 (FIG. 6).

Each of the two plates plate 11 has a flat plate shape, and is attached to the body frame 15. Each of the four vertical frames 12 is attached to have a columnar shape, and the plate board 11. Each of the four vertical frames 12 extends from the mounting position to the plate board 11 to the upper side of the engine 10.

Horizontal frame 13 is attached to the vertical frame 12 has two frame portions, for example, separated in the Y direction. One of the two frame portions of the transverse frame 13 is a portion for supporting the diesel particulate filter device 3 and selective catalytic reduction device 4 of the assembly 2a, the two frame portions of the other assembly 2b diesel particulate a portion for supporting the collecting filter device 3 and selective catalytic reduction device 4.

Each of the two sub-bracket 14 has a flat plate shape. One of the two sub-bracket 14 is attached to one of the two frame portions of the lateral frame 13, and the other two sub-bracket 14 is attached to the other of the two frame portions of the lateral frame 13.

A plurality of small bracket 141, and two brackets for supporting the two brackets supporting the diesel particulate filter device 3 of the assembly 2a, the selective catalytic reduction device 4 of the assembly 2a, capturing diesel particulate assembly 2b It consists two brackets for supporting the collecting filter device 3, and two brackets for supporting the selective reduction catalyst device 4 of the assembly 2b.

The bracket for supporting the bracket and assembly 2a selective reduction catalyst device 4 for supporting the assembly 2a diesel particulate filter device 3 is attached to one of the two sub-bracket 14. The bracket for supporting the bracket and selective catalytic reduction device 4 of the assembly 2b for supporting the diesel particulate filter device 3 of the assembly 2b is attached to the other of the two sub-bracket 14.

Engine 10 and exhaust treatment structure 1 by rubber dampers 16 and supporting structure 20A as described above is supported on the body frame 15 independently of one another. Rubber-damper 16 may be attached to the plate board 11 of the supporting structure 20A, or may be attached to the body frame 15.

It will now be described with reference to FIGS. 4 and 9 the structure for supplying urea to the selective reduction catalyst device in the exhaust processing structure.

Figure 9 is a schematic perspective view showing a configuration of the mixing pipe and the urea water tank exhaust treatment structures (reducing agent tank) are connected by urea water piping (reducing agent pipe). Referring to FIG. 9, the selective reduction catalyst device 4 is for reducing selectively NOx NO x for example by hydrolyzing urea water. This requires a device for supplying urea to the selective reduction catalyst device 4.

The urea supply device is provided with a urea water tank 21, a pump 22, mainly has a urea water pipe 23.

Urea water tank 21 is configured to be able to store urea water. The urea water tank 21, for example, is disposed outside the engine room is supported on the body frame 15.

Urea water pipe 23 connects the urea water tank 21 and the mixing pipe 5. It is possible to direct the urea water stored in the urea water tank 21 into the interior of each of the two mixing pipes 5 by urea water pipe 23.

Pump 22 is disposed in the middle path of the urea water pipe 23. The pump 22 is to make the role of feeding the respective to the urea water of the two mixing pipes 5 through the urea water pipe 23 from the aqueous urea tank 21.

By driving the pump 22 of the urea feeder, urea water is stored in the urea water tank 21 is injected and supplied to the inside of each of the two mixing pipes 5 through the urea water pipe 23.

In the above urea supply device is connected from the same side in the longitudinal direction (X direction) to each of the urea water pipe 23 is two mixing pipe 5 as shown in FIG. 4 (in the figure the front side). Connection to the mixing pipe 5 of the urea water pipe 23 is upstream of the exhaust passage in the mixing pipe 5. Thus, the mixing pipe injection-supplied urea water into the 5 mixes evenly with exhaust while extending from the upstream side of the mixing pipe 5 to the downstream side.

Although the exhaust treatment structure 1 as shown in FIG. 5 describes the configuration that is arranged offset portion from directly above the region of the engine 10 in the above, the entire exhaust treatment structure 1 as shown in FIG. 10 or it may be located directly above the area of ​​the engine 10.

In the configuration shown in FIG. 10, two sets of assemblies 2a, 2b are, diesel particulate filter device 3 of the first set of assembly 2a, selective catalytic reduction device 4 of the first set of assembly 2a, selective catalytic reduction device 4 of the second set of assemblies 2b, and are arranged so as to line up in the order of diesel particulate filter device 3 of the second set of the assembly 2b.

The first and second connecting pipes 7a, 7b each, including two selective reduction catalyst device 4 is connected to the diesel particulate filter device 3 through the region directly below arranged arrangement region R2.

Since the configuration other than the above shown in FIG. 10 is substantially the same as those shown in FIGS. 1-9, the same reference numerals are given to the same elements, and description thereof is not repeated.

The configuration has been described in which the exhaust treatment structure 1 and the engine 10 as shown in FIGS. 6 to 8 are supported on the body frame 15 independently of one another in the above, the exhaust processing structure as shown in FIG. 11 1 may be supported in the engine 10 by interposing a support material 20B. Supporting structure 20B in this configuration, for example, has a support base 25 for supporting the exhaust treatment structure 1 by the engine 10 above, and a connecting portion 26 for connecting the support base 25 to the engine 10 there. The connecting portion 26 is joined to the engine 10 such as bolts or the like.

In the configuration shown in FIG. 11, two sets of assemblies 2a, 2b are diesel particulate filter device 3 of the first set of assembly 2a, selective catalytic reduction device 4 of the first set of assembly 2a, selective catalytic reduction device 4 of the second set of assemblies 2b, and are arranged so as to line up in the order of diesel particulate filter device 3 of the second set of the assembly 2b.

The first and second connecting pipes 7a, 7b each of the two selective reduction catalyst device 4 is connected to the diesel particulate filter device 3 through the region directly below arranged placement area.

Since the configuration other than the above shown in FIG. 11 is almost the same as those shown in FIGS. 1-9, the same reference numerals are given to the same elements, and description thereof is not repeated.

It will now be described with reference to FIGS. 12 to 15 the arrangement of such an air cleaner connected to an intake side of the engine.

Figure 12 is a schematic perspective view showing a state in which the air cleaner is connected to the intake side of the engine from the oblique rear. Referring to FIG. 12, the intake side of the engine 10 air cleaner 27 interposed the pipe 29 is connected. The air cleaner 27, the air taken into the engine 10, and filtered with a filter is used for foreign matter such as dust is prevented from being mixed into the combustion chamber.

The air cleaner 27 is disposed at a distance for example on the side of the exhaust treatment structure 1 (Y-direction). Specifically, the air cleaner 27 are arranged at intervals next to the diesel particulate filter device 3 of the assembly 2b in plan view. Umbrella portion 28 is provided so as to cover the intake Prompt of the air cleaner 27.

The air cleaner 27 may be externally attached to the outside of the engine hood 31b as shown in FIG. 13. In this arrangement, umbrella portion 28 so as to cover the intake Prompt the air cleaner 27 is located outside of the engine hood 31b.

The air cleaner 27 may be furnished on the inner side of the engine hood 31b as shown in FIG. 14. In this configuration, air inlet of the air cleaner 27 is open upwardly, the umbrella portion 28 so as to cover the intake Prompt is located outside of the engine hood 31b.

The air cleaner 27 is furnished inside the engine hood 31b as shown in FIG. 15, the umbrella portions may be omitted. In this configuration, the inlet port 31b 2 on one side or lateral side surface of the front side of the engine hood 31b is provided.

Next, the function and effect will be described in this embodiment. According to this embodiment, the two assemblies 2a as exhaust treatment structure 1, since 2b is provided, it is possible to increase the exhaust gas treatment capability, sufficient even in a working vehicle equipped with the engine 10 of large it can be obtained Do exhaust gas treatment capacity.

Further, as shown in FIG. 4, the longitudinal direction B1 each of each of the two selective reduction catalyst device 4 of the exhaust tube 6 is provided, and two exhaust tube 6 in each of the two selective reduction catalyst device 4 adjacent to each other , are arranged on (the side opposite to the intake port 5b) the same end side in B2. Therefore, it is possible to approach the position of the two exhaust pipe 6 with each other, the flow direction of the exhaust gas is likely to be grasped, it is easy to set the intake position evacuated to a suction difficult position of the engine 10.

Further, as shown in FIG. 1, it can be arranged close to each other holes 31b 1 for two exhaust tube provided in the engine hood 31b to pass each of the two exhaust pipe 6. Therefore, it is possible to simplify the configuration of the engine hood 31b, which facilitates manufacture of the engine hood.

Further, as shown in FIG. 4, the diesel particulate filter device 3 and selective catalytic reduction device 4 of the assembly 2a, they are spaced apart at a distance GA in plan view. The assembly 2a selective reduction catalyst device 4 and the assembly 2b selective reduction catalyst device 4 of, are spaced apart at a distance GB in a plan view. An assembly 2b selective reduction catalyst device 4 and the diesel particulate filter device 3 are spaced apart at a distance GA in plan view. Thus it is possible to arrange packed with intervals each structural unit 3,4 with each other.

Further, as shown in FIG. 4, the spacing GA assemblies 2a, each of the diesel particulate filter device 2b 3 and selective catalytic reduction device 4, each of the spacing GB between 4 selective reduction catalyst device, the two each of the diameter of the mixing pipe 5 D1, smaller than D2. It is possible thereby to place stuffed constituent devices 3 and 4 of the exhaust treatment structure 1 in the Y direction, it is possible to arrange the exhaust treatment structure 1 compact.

The first and second connecting pipes 7a as shown in FIG. 5, each 7b, via the region directly below the arrangement region R2 including two selective reduction catalyst device 4 is arranged, diesel particulate filter device It is connected to the 3. Thus, first and second connecting pipe 7a, by routing the 7b, first and second connecting pipe 7a, while placing 7b on the lower side of the exhaust treatment structure 1 the first and second connecting pipes 7a , it is possible to ensure a long length of 7b. Therefore, an error in the position of the engine 10 by the deflection of the supporting structure 20A by machining and assembly errors, and the weight of the exhaust treatment structure 1 supports at 20A for supporting the exhaust treatment structure 1 and the exhaust treatment structure 1 even when generated, first and second connecting pipes 7a, 7b of length and extendable bellows portion 7aa, by and 7ba can be absorbed the error. Thus two assemblies 2a, also in the configuration where 2b is provided, it is easy to connect the engine 10 and the exhaust processing structure 1.

The first and second connecting pipe 7a, since the length of 7b can ensure a long, the first and second connecting pipes 7a, 7b of length and extendable bellows portion 7aa, and vibration of the vehicle body frame 15 by a 7ba it is possible to absorb vibration difference between the vibration of the engine 10. Therefore, two assemblies 2a, also in the configuration where 2b is provided, the first and second connecting pipe 7a, the load due to the vibration difference 7b is prevented from acting.

The first and second connecting pipe 7a, since the length of 7b can be secured long bellows portion 7aa, it becomes easy to increase the length of 7ba. This makes it easier to absorb the error and vibration difference of the position.

The first and second connecting pipes 7a as shown in FIG. 5, 7b each of the engine 10 side of the connection end 7ab of, 7bb are located directly below the region R1 of the exhaust treatment structure 1. That the connection end 7ab, 7bb are located either directly below the area of ​​the region R23 between the region directly below the assembly 2a, beneath the region of the assembly 2b, and an assembly 2a and assembly 2b. Thus the length of the first and second connecting pipes 7a, 7b each of the engine 10 side of the connection end 7ab of, since it is possible to close the exhaust treatment structure 1 7bb, first and second connecting pipes 7a, 7b while ensuring a longer becomes possible to arrange the engine 10 exhaust treatment structure 1 compact.

The first and second connecting pipes 7a as shown in FIG. 5, 7b each of the engine 10 side of the connection end 7ab of, 7bb are two region directly below the selective reduction catalyst device 4 like are arranged arrangement region R2 It is located in. That the connection end 7ab, 7bb is selected region directly below reducing catalyst device 4 of the assembly 2a, beneath the region of the selective reduction catalyst device 4 of the assembly 2b, and assemblies 2a selective reduction catalyst device 4 and the assembly 2b It is located either directly below the area of ​​the region R23 between the selective reduction catalyst device 4. Thus the length of the first and second connecting pipes 7a, 7b each of the engine 10 side of the connection end 7ab of, since it is possible to approach the selective reduction catalyst device 4 7bb, first and second connecting pipes 7a, 7b while ensuring a longer becomes possible to arrange more compact and exhaust treatment structure 1 and the engine 10.

Also as shown in FIGS. 6 and 7, the engine 10 and the exhaust treatment structure 1 is supported by the body frame 15 independently of each other. Thereby installed independently of each other between the engine 10 and the exhaust treatment structure 1, or it becomes possible to remove, installation and maintenance is facilitated.

The exhaust processing structure 1 as shown in FIG. 11 when it is supported by the engine 10, it is possible to arrange the exhaust treatment structure 1 and the engine 10 compactly.

Further, as shown in FIG. 4, two diesel particulate filter device each longitudinal A1, A2 of 3 in the case of parallel to each other in plan view, the two diesel particulate filter device 3 of the intake port 3a each of which is arranged to include a plane C of the virtual orthogonal to both the longitudinal direction A1, A2. Whereby the first and second connecting pipe 7a, it is easy to connect each 7b in diesel particulate filter device 3, the assembly and maintenance is facilitated.

Also in the plan view shown in FIG. 4, diesel particulate filter device 3 and selective catalytic reduction device 4 of the assembly 2a, to the imaginary straight line D extending in the longitudinal direction in between the two selective reduction catalyst device 4, the set It is disposed diesel particulate filter device 3 and a selective reduction catalyst device 4 and the line symmetry of the three-dimensional 2b. Which facilitates the design of exhaust treatment structure 1.

Also as shown in FIGS. 4 and 9, are connected urea water pipe 23 from the same side in the longitudinal direction of each of the two mixing pipes 5 (upper side in the drawing). This makes it easy to maintain the temperature of the urea water supplied to the mixing pipe 5 to the appropriate temperature. It will be described below that.

Referring to FIG. 9, the urea is stored in the urea water tank 21 water is suitable temperature control is required. Specifically, since the temperature in the urea water tank 21 the ammonia is easily generated from the urea water in the urea water tank 21 exceeds 50 ~ 60 ° C., the urea water tank 21, avoiding environmental of having a high temperature it is preferably arranged Te. Since the engine compartment is that a relatively high temperature due to the heat generated by such an engine 10, along with the urea water tank 21 is arranged so as to avoid an engine room, the urea water pipe 23 is the engine room from the urea water tank 21 until it reaches the mixing pipe 5 it is preferable to shorten the path length through the internal utmost.

In the present embodiment here, the urea water tank 21 is disposed outside the engine room. The urea water pipe 23 is connected from the longitudinal same side of each of the two mixing pipes 5. Further, the portion which is connected to its urea water pipe 23 and mixing pipe 5 are the same side as the arrangement side of the urea water tank 21 to the engine room. Thereby, it becomes possible to shorten the path length urea water pipe 23 passes through the engine compartment. Therefore, the urea water flowing through the urea water pipe 23 is less susceptible to heat in the engine room, it is easy to keep the temperature of the urea water supplied to the mixing pipe 5 to the appropriate temperature.

Also because it is connected the urea water pipe 23 from the two mixing pipes 5 each longitudinal same side of the (upper side in the drawing), it is possible to simplify the piping path of the urea water pipe 23.

Further, as shown in FIG. 4, the urea water pipe 23 is connected to the upstream end of the exhaust path in the mixing pipe 5. Therefore, the injection-supplied urea water into a mixing pipe 5 consists of the upstream end of the mixing pipe 5 can be uniformly dispersed in the exhaust to reach the downstream end.

Also in the plan view shown in FIG. 4, the gap between the diesel particulate filter device 3 and selective catalytic reduction device 4 of the assembly 2a overlaps the mixing pipe 5. Also in the plan view shown in FIG. 4, the gap between the diesel particulate filter device 3 and selective catalytic reduction device 4 of the assembly 2b overlaps the mixing pipe 5. It is possible thereby to place stuffed constituent devices 3 and 4 of the exhaust treatment structure 1 in the Y direction, it is possible to arrange the exhaust treatment structure 1 compact.

Further, as shown in FIG. 5, the bellows portion 7aa includes two bellows parts, and includes also two bellows portions bellows 7ba. Thus, it is possible to prevent the resonance, the first and second connecting pipe 7a, are 7b each connection becomes easy.

Further, as shown in FIG. 5, the second connection pipe 7b has a portion folded back in the opposite direction from its one-way side from the connection end 7ab of the engine 10 side after extending in one direction side of the Y-direction . By having such a portion where the second connection pipe 7b wraps can while the second connection pipe 7b is arranged below the exhaust treatment structure 1 to ensure a long length of the second connecting tube 7b to become.

The embodiments disclosed herein are to be considered as not restrictive but illustrative in all respects. The scope of the invention is defined by claims rather than the above description, it is intended to include any modifications within the meaning and range of equivalency of the claims.

Claims (4)

And the engine, A first exhaust gas treatment apparatus for treating exhaust gas from the engine, A second exhaust gas treatment apparatus for treating exhaust gas having passed through the first exhaust treatment device, Third and exhaust treatment device for treating exhaust gases from said engine, A fourth exhaust gas treatment apparatus for treating exhaust gas having passed through the third exhaust treatment device, A first exhaust pipe extending upward from the outlet of the second exhaust treatment device, A second exhaust pipe which extends upwardly from the outlet port of the fourth exhaust treatment device, Equipped with a, Wherein the first to fourth exhaust treatment device, so that each longitudinal direction is parallel, the first exhaust treatment apparatus, the second exhaust treatment apparatus, the fourth exhaust treatment device, the order of the third exhaust treatment device in side-by-side are arranged, Wherein each of the second exhaust pipe of the second the first exhaust pipe of the exhaust gas treatment apparatus fourth exhaust treatment apparatus, the longitudinal direction and the length of the fourth exhaust treatment device of the second exhaust treatment device They are arranged side by side on the same end side in the direction, the engine unit.

The first exhaust treatment device and the second exhaust treatment device, wherein the second exhaust treatment device fourth exhaust treatment device, and the distance, respectively a plan view and the fourth exhaust treatment device and the third exhaust treatment device It has been are spaced apart, the engine unit according to claim 1.

A first relay connecting pipe for connecting between the first exhaust treatment device and the second exhaust treatment device, And a second relay connecting pipe for connecting between the third exhaust treatment device and the fourth exhaust treatment device, In plan view, wherein the first exhaust treatment device the distance between the second exhaust treatment device, the second interval of the exhaust treatment device and the fourth exhaust treatment device, and the third exhaust and the fourth exhaust treatment device each interval between the processor, the smaller than the diameter of the first diameter of the intermediate connecting pipe and the second relay connecting pipe, an engine unit according to claim 1 or 2.

Wherein having an engine unit, a work vehicle according to any one of claims 1 to 3.